Effects of L-arginine and L-NAME on ischemia-reperfusion in rat liver

ABSTRACT

PURPOSE: To evaluated the effects of L-arginine (a NO donor) and L-NAME (Nw-nitro-L-arginine methyl ester - a NOS inhibitor) on ischemia-reperfusion in rat livers.METHODS: One hundred fifty two male Wistar rats were divided into four groups control (simulated surgery); hepatic IR; pretreatment with L-arginine plus hepatic IR; and L-NAME plus hepatic IR. The hepatocellular damage was evaluated at the first, third and seventh days after the procedures through the alanine-aminotransferase (ALT) and aspartate-aminotransaminase (AST) levels, as well as histopathological features vascular congestion (VC); steatosis (STE); necrosis (NEC); and inflammatory infiltration (INF). The mortality rate was also evaluated.RESULTS: The pretreatment with L-NAME significantly worsened the AST levels after hepatic IR (p 0.05) at first day and L-arginine demonstrated an attenuating effect on ALT levels at seventh day (p 0.05). Furthermore, the administration of L-arginine was able to reduce the VC and STE in the seventh day after hepatic IR (p 0.05). The analysis of the mortality rates did not demonstrate any difference between the groups. Nevertheless, there was not effect of L-arginine and L-NAME on the mortality of the animals.CONCLUSION: L-arginine/NO pathway has a role in the hepatic IR because the pretreatment with L-arginine partially had attenuated the hepatocellular damage induced by hepatic IR in rats.(AU)